ALTER TABLE Book
ADD PublisherID int

ALTER TABLE Book
DROP COLUMN Publisher

ALTER TABLE [dbo].[Book]  WITH CHECK ADD  CONSTRAINT [FK_Book_Publisher] FOREIGN KEY([PublisherID])
REFERENCES [dbo].[Publisher] ([ID])
GO
ALTER TABLE [dbo].[Book] CHECK CONSTRAINT [FK_Book_Publisher]
GO

UPDATE Book 
SET Book.PublisherID = Publisher.ID
FROM Book 
INNER JOIN dbo.Publisher
ON Book.Publisher = Publisher.Name